task1 PC hardware

PC HARDWARE

TASK1

Computer is a fast electronic device that processes the input data according to instructions given by programmer/user and provides the desired information as output.

Or

Computer is a high speed electronic device that accepts and stores data and instructions, processes the data and produces the desired output.

Or

Computer is an advanced electronic device that takes raw data as input from the user and processes these data under the control of set of instructions (called program) and gives the result (output) and saves output for the future use.

COMPUTER STANDS FOR: Computation Oriented Machine for Processing Utility Trade Education and Research.

Functional units of computer

Characteristics of Computer:

•      High Memory

•      Fast

•      Accurate

•      Diligence

•      Reliability

•      Networking Capacity

•      Versatility -> computers can be used in many areas like business, schools, home, making movies etc.

Applications of Computer

•      Business

•      Finance

•      Defense and Military

•      Medical

•      Engineering

•      Transportation

•      Banking

•      Educational

•      And Many more…………

Block Diagram of a Computer

Computer System

A Computer System is a Collection of hardware and software components designed to perform computations very effectively.

Computer System consists of four parts:

•      Hardware :- Physical Components

•      Software : - Set Of Instructions

•      People : - Computer Operators/users

•      Data : - It consists of raw facts which the computer stores and reads in the form of numbers (0’s and 1’s).

It is made up of 2 major components. They are: 1) Hardware. 2) Software

 

Hard ware

•      It refers to any physical component of computer.  Hardware is the part of the computer that we can touch and feel.  It is made up of interconnected electronic devices that control the operations of the computer.

•      A Computer system has the following hardware components.

•      Motherboard, input device, output devices, Storage devices, Cards, Ports and Cords, power Supply, Processor, Memory.

Software

•      It refers to the programs to run the computer.  Software is a group of instructions that tell the hardware what to do.  These instructions are also called programs. 

•      Ex: Java, MS Office , C, C++, Oracle etc.

•      Software is the collection of programs that enables the hardware to process the data.

Input Devices:

Ø These are used to enter data and programs into computer

Ø These are for man to machine communication

Ø Ex: Keyboard, mouse, scanner, touch sreen, audio input.

Output Devices:

Ø These are used to get the desired output from the computer

Ø These are for machine to man communication

Ø Ex: Printer, Monitor, Speakers

Ø If the output is shown on monitor then it is called “soft copy”

Ø If the output is printed on a paper using printer then it is called “hard copy”.

CPU(Central Processing Unit)

Ø It is responsible for processing the instructions

Ø It consists of 3 parts

1)    ALU – Arithmetic & Logic Unit

2)    CU – Control Unit

3)    Memory

Ø ALU performs arithmetic operations like addition, subtraction, multiplication, division and logical operations like comparisons among data

Ø CU is responsible for movement of data inside the system

Ø Memory is used for storage of data and programs. It is divided into 2

1)    Primary Memory / Main Memory

2)    Secondary Memory / Auxiliary Memory

1)      Primary Memory

 

Ø It is also called main memory

Ø Data is stored temporarily i.e. data gets erased when computers is turned off

Ø Ex: RAM

2)    Secondary Memory

Ø It is also called as auxiliary memory

Ø Data is stored permanently so that user can reuse the data even after power loss.

Ø Ex: Hard disk, CD, DVD, Floppy etc.

BUS

—  It is nothing but electronic path way

                     Width ----- bits

                      Speed ----- MHZ

—  It carries information between one device to another

Processor

•      A processor is a brain of computer. It is also known as a CPU (central processing unit).

•      Processor is made up of transistors and registers.

•      It is used to execute all the instructions and calculations inside the computer.

•      Processors are two types:

                    a) Slot type b) socket type

Specification of Processor

1)    Speed (Hz) i.e., Hertz  is a Unit of frequency

2)    Width (Bits) i.e., Smallest Unit

Speed :- The time taken by the processor  to  Executes  Program(set of instructions).

Width :- How much data it can transfer  at a time

Generation of Processor

                       Processor                                   Speed

          

                    P-I/P.Pro                              100 MHZ to 230 MHZ

                  Celeron/P-II/Xeon                 230 MHZ to 450 MHZ

                 Celeron/P-III/Xeon                450 MHZ to 1.3 GHZ

                  Celeron/P-IV/Xeon                 1.3 GHZ to 4.2 GHZ

     Celeron (Desktop side and Low Cache Memory)

     Pentium – I , II , IIII , IV ( Desktop side and Medium  Cache  Memory)

     Xeon     (Server side and High Cache Memory)

   

Cache Memory 

—  It is Intelligent Memory.

—  It acts interfaces between RAM and Processor , recently (or) used applications will be store in Cache Memory

—  Cache memory (also called buffer memory) is local memory that reduces waiting times for information stored in the RAM (Random Access Memory).

Primary Storage Devices(RAM and ROM)

—  RAM à Random Access Memory):- Temporary Memory.

    RAMs are:

   SD-RAM   à Synchronous Dynamic-RAM (Desktop side)

   DDR-RAM à Double Data Rate-RAM (Desktop side)

   RD-RAM    à Rambus Dynamic-RAM (Server side)

•      ROM (BIOS: Basic Input Output System) à Read Only memory:- Permanent Memory. It is non-volatile which means once you turn off the computer the information is still there.

Different Types Of ROM chips

1.    PROM : -  (Programable ROM)

      à We can’t erase the program

2.   EPROM: - ( Erasable PROM)

      à We can erase the program

3.    EEPROM: - (Electrically EPROM)

      à  We can erase the program

MOTHER BOARDS (OR) SYSTEM BOARDS

    The motherboard is the main circuit board in a computer.

    

    A motherboard provides a way for hardware in a computer to communicate with each

     Other.

   

Magnetic Storage Devices

Hard disk : Storage device. These are two types

1.    ATA (Advance Technology  Atachment)(Desktop side).

2.    SCSI(Small Computer  System  Interconnection (or) Interface(Server side).

      ATA is two types:

1. PATA: Parallel  ATA, No.of pins=40, IDE Cable, DTR-150 mbps. DTR means Data Transmission Rate.

2. SATA : Serial ATA, No.of pins=7, SATA Cable, DTR-300, 600 mbps.

      SCSI are SCSI-I, SCSI-II, SCSI-III, DTR-600, 900 mbps

Optical Storage Devices

CD - Compact Disk : Different Capacities in CD’s

    Single Sided Single Layer – 700 MB

    Single Sided Dual Layer – 800 MB

DVD – Digital Versatile Disk : Different Capacities in DVD’s

    DVD’5 Single Sided Single Layer – 4.7 GB

    DVD’9 Single Sided Dual layer – 8.4 GB

    DVD’10 Dual Sided Single Layer – 9.5 GB

    DVD’18 Dual Sided Dual Layer – 17.1 GB

    HD-DVD(Hard Disk-DVD) (or) AOD(Advanced Optical  Disk): Double Sided Triple Layer – 45 GB

BRD – Blue Ray Disk – 200 GB

    BRD 27 Single Sided Single Layer – 27 GB

    BRD 54 Single Sided Dual Layer – 54 GB